Mechanism and swimming experiment of micro mobile robot in water

This paper deals with a micro mobile robot in water utilizing a PZT(Pb(Zr,Ti)O₃) as an actuator. A robot driven by a PZT requires a magnification mechanism and the effect of the resonance condition to enlarge the displacement of the PZT to some extent. We show a structure for the magnification mechanism, which is made by the wire cut method. The magnification ratio is 326 geometrically. We propose a prototype micro mobile robot in water which possesses a pair of fins and moves them symmetrically. Therefore, the momentum of this robot is canceled and the tendency to move straight ahead is improved. The mechanism and the principle of the robot that is devised considers the problems in former research. We prove the effectiveness of the mechanism and the propulsion principle by using a pair of fins both theoretically and experimentally through computer simulations and swimming experiments in fluid. The size of the robot is 50 mm in length and 6 mm in width. This robot has many possible applications, such as small pipeline inspections and use in bio medical fields